Sizing apparatus.



narran enanas sanear onirica.,

HARRY W. HARDINGE, 0F NEW YORK, N. Y., ASSIGNOR TO HARDINGE CONIGAL MILL l COMPANY, OF NEW YORK, N. Y., A CORPORATION 0F NEW YORK.

SIZING- APPARATUS.

are afterward to be subjected, and in some' cases the proportion of particles of excessive size is so large as to cause an appreciable loss of values. If the attempt is made to obviate the diliiculty by subjecting the entire material to longer or more powerful grinding action we are met -bythe fact that the output of the machine per unit of time is vreduced or the amount of power consumed is increased, or both; and, moreover, in thus minimizing the proportion of particles that are too large the proportion of particles that are or may be too small is :increased` The best solution of the problem is to remove from the disintegrated material the large particles so that they can be-returned to the grindingapparatus for further reduction.

My present-invention is designed to provide a simple, cheap, and withal thoroughly eiiiective apparatus for thus separatingv the larger particles from the smaller, and, preferably, also returning the former to the grinding or disintegrating mill for further grinding.

To these and otherends the invention consists inthe novel features of construction and combinations of elements hereinafter described and claimed.4 j j In its preferred form, my invention comprises a rotary container or receptacle from which the disintegrated material is discharged in the form of fine particles. This receptacle may be the tube mill in which the grinding is done, in which case I employ preferably a conical mill of the type described in my prior patent No. 908,861, dated January 5, 1909, as it has been found by experience that in a well. designed mill of that type the percentage of excessively.

Specification of Letters Patent.

Patented Aug. 10, 1915.,

application led December 23, 1914. Serial No. 878,810.

llarge particles is smaller under similar conditions of use than in other types of mills in common use. The receptacle referred to, for 'example aiconical grinding mill, is provided with an outlet element of tubular form, preferably cylindrical, which outlet element is usually one of the trunnions on which the mill revolves. The inner surface of such trunnion is provided with a plurality of pockets, channels, or grooves, eX- tending in a' generally axial direction and preferably formed by ribs or narrow blades attached to the said inner surface. As the disintegrated material is discharged, being carried by flotation on a stream of water flowing through the mill, most of the large vparticles. which find their way to a point near the inner orifice of the outlet trunnion are too heavy to float and so sink back into the mill; but others, buoyed up by the outilowing slime, enter the trunnion and, although as they move along they may be settling to the bottom of the stream, their downward progress is slow, and hence, with the ordinary form of outlet trunnion, they are carried on out and are discharged. With the ribs or grooves in the trunnion, as provided in my scheme, the revolving grooves carry the outwardly flowing material upwardly and permit only the surface stratumof the stream. to escape at once, thus 'ving the larger particles ample time to sin r wel] below the surface. Then, at a suitable point, the grooves come into the path of a vjet of water -or other fluid directed toward the interior of the mill, with the result that the material carried up by the grooves or ribs, composed for the greater part 'of particles too coarse to float on the surface of the water, are propelled `or washed back into the mill for further subjection to the grinding or disintegrating process there going on.

In the accompanying drawing I have illustrated, somewhat diagrammatically, an apparatus embodying the above features and operating as described.

Referring now to the drawing, Figure l described in Vmy prior patent above mentioned, has an inlet trunnion. 1 1 andan outlet trunnion 1,2 mounted rotatably 1n suitable vbearings on the standards or Asupports d3, lhgfThe mill or drum 10 is rotatedby meansfof a gear 15., fixed adjacent to the inlet trunnion and driven by` any suitable means, not shown, gratedA cre or other material is discharged into: the mill, along witha stream of water, bymeans of an inlet chute'lextending into the'V inlet trunnion, and the finely divided material issues from the outlet trunnion' into a suitable launder 17. As shown lmore clearly in Fig. 2, the inside of the outlet trunnion is provided with a series of longitudinally extending ribs 18,

secured to the trunnion in any convenient manner and, --preferably, inclined as shown,

that is, toward the direction of rotation of the trunnion, which direction in the present instance is counterclockwise, as seen in nion they are carried up .and out of the stream by the blades or ribs 18. The trun nion and ribs being approximately horizontal, as preferably they are, the material carried up and out of the stream is no longer urged forwardby material behind it and` hence, except 'for the -momentum already achieved, would have as great a tendency to flow back into'the mill as to flow out into the launder 17. Hence the rate of flow toward the outlet end of the trunnion is lessened rather than increased, with the result that most of the larger particles would be carried a considerable distance upwth the 66] ascending side of the trunnionv before escaping. At a lsuitable point, for example just above the horizontal diameter thereof, 1s a .Jet pipe 19, connected with any' convenient source of water, compressed air, or other 501 suitable Huid not shown, and directed to:

ward the ascending side of the trunnion and also slightly downward. The more` or less powerful jet of water discharged from this pipe strikes thematerial carried up by v551 the ascending channels and washes it back into the barrel l0, Where the material is engulfed in the violently churning or agi'- tated contents of the revolving barrel. In this way the greater part of the coarse mate- @Ui rial whichy finds its way into the outlet trunnion is returned to the barrel, while most of the slime flows. out of the. trunnion before the ascending ribs reach the path of the water'jet. In other words, the slime discharged into the launder 17 contains only a rIhe partially disintebarrel instead of back into it.

small proportion of coarse particles, while the coarse particles Washed back into. the

- barrel are accompanied by only a relatively small amount of slime. Hence the eliiciency of the apparatus is not decreased, but in fact may be actually increased, since the outflow, though slightly reduced in volume,

containsfewer particles that cannot be advantageously utilized (if utilizable'at all) because of their excessive size. Ofcourse if the jet pipe 19 discharges outwardly the particles carried up by the ascending side of the trunnion will be washed out of the It is to be understood that the invention is not confined tothe construction herein specilically illustrated, but. can be embodied in other forms without departure from its proper spirit and scope.

What I claim-is:

1. In an apparatus for the purpose set forth, a rotary tubular outlet member for the outflow of disintegrated material, having on its 4inner surface a plurality of channels extending in a generallylongitudinal direction', and means above the outowing `material for discharging fluid into the channels in a direction opposite to that of the outflowing material.

2.'In an apparatus .for the purpose set forth, a rotary tubular outlet member for the outflow of disintegrated material having on its inner surface a plurality of chan'- nels extending in a generally longitudinalk direction, and a jet'pipe arranged to discharge fluid inwardly into the channels above the surface ofthe material owing out through said tubular member as the latter A rotates.

3. In an apparatus for the purpose set forth, a rotary .tubular outlet member having on its inner surface a plurality of ribs extending in agenerally longitudinal di rection, and a jet pipe above the bottom of the outlet member and at the ascending side of the same, arranged to direct a jet of fluid into the channels formed by said ribs as they pass the outlet orifice of said pipe.

4. The combination with a rotary receptacle having a rotary tubular outlet member, of means for directing a jet of iuid in' a substantially axial direction upon the as` cending side of the member inside the same.

5. The combination with a rotary grinding mill having'a rotary outlet member, of means revolving with the outlet member inside the same to separate coarse particles from the disintegrated material flowing out through said member, and a jet pipe arranged to discharge a jet of fluid upon the said lcoarse particles and propel the same back into the grinding mill. p

6. The combination with a rotary grinding mill, a rotating tubular outlet member therefor having on its inner surface a plurality of longitudinally extending channels, and a jet pipe arranged to discharge a jet of fluid backwardly into said channels after they have passed the bottom of their path and as they are rising with the ascending side of the outlet member.

In testimony whereof afx my signatlire in the presence of two subscribing witnesses. 

